Heat development, in which the developing process is conducted under heating conditions, is a well-known technique; as a means of obtaining a color image, the so-called the transfer type heat-processable light-sensitive material, in which a dye image is transferred from the light-sensitive material to the image-receiving layer, is also known well.
To suppress fogging occurring in the heat developing process, many antifogging techniques for heat-processable light-sensitive materials and dye-receiving materials have been disclosed. However, almost all of such techniques have drawbacks, including those related to storage quality such as storage stability deterioration in the heat-processable light-sensitive material and dye-receiving material and degradation of the antifogging effect during storage, and sensitivity reduction, great reduction of contrast, maximum density reduction, heat processablity and dye transferability reduction and unstable production of the heat-processable light-sensitive material.
Another problem in heat development at high temperature is that chemical sensitization must be completed at a point fairly lower than the maximum sensitivity to be reached because even the formation of a very small number of fogging nuclei results in increased D.sub.min in chemically sensitizing the grain surface of silver halide photographic emulsion. However, when the degree of chemical sensitization is lowered to have sufficiently low fogging, not only is the sensitivity lowered but also the heat-processable light-sensitive material contrast is lowered. In addition, the silver halide emulsion subjected to such limited chemical sensitization was found to easily undergo considerable contrast reduction on the shoulder (high density region) on the characteristic curve in short-time exposure because luminance intensity increases.
For this reason, it is preferable to be as close to the maximum sensitivity as possible in chemical sensitization of the grain surface of silver halide emulsion, but it has been difficult to reach a sufficient level because of a rise in D.sub.min.
In this situation, there has been a demand for an antifogging technology wherein the maximum density is hardly affected, fogging is effectively suppressed, photographic performance is hardly affected and a heat-processable light-sensitive material is stably produced and coating solution retention is good.
Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) Nos. 118155/1988 and 144350/1988 disclose a heat-processable light-sensitive material and a dye-receiving material wherein D.sub.min is lowered with almost no effect on D.sub.max by the addition of particular compounds substituted by a halogen atom. However, this method was found faulty in that these compounds decompose partially and the antifogging effect is slightly degraded when the heat-processable light-sensitive material or dye-receiving material is stored for a long time, particularly under high moisture conditions, though they offer excellent improvement in D.sub.max /D.sub.min. Also it was found that in producing a heat-processable light-sensitive material or dye-receiving material containing such compounds, the coating solution containing them, if retained for a long time, tend to lower the antifogging effect. In addition, these compounds are insufficient to enhance contrast on the characteristic curve, though they are sufficiently suppress fogging.
Japanese Patent O.P.I. Publication No. 223852/1991 discloses a heat-processable light-sensitive material and dye-receiving material containing a compound which reacts with anisidine at a particular reaction rate, and describes that the use of such a compound provides a heat-processable light-sensitive material with suppressed stain and desensitization due to fogging and suppressed increase in aging stain in the transferred image.
However, even when such a compound is added to the heat-processable light-sensitive material or dye-receiving material, the antifogging effect in the heat-processable light-sensitive material is insufficient, and when such a compound is added to the heat-processable light-sensitive material, fogging occurring during light-sensitive material storage is not sufficiently suppressed.